trunk/src/files.c

/***************************************
 $Header: /home/amb/CVS/routino/src/files.c,v 1.23 2010-10-09 18:20:18 amb Exp $

 Functions to handle files.

 Part of the Routino routing software.
 ******************/ /******************
 This file Copyright 2008-2010 Andrew M. Bishop

 This program is free software: you can redistribute it and/or modify
 it under the terms of the GNU Affero General Public License as published by
 the Free Software Foundation, either version 3 of the License, or
 (at your option) any later version.

 This program is distributed in the hope that it will be useful,
 but WITHOUT ANY WARRANTY; without even the implied warranty of
 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 GNU Affero General Public License for more details.

 You should have received a copy of the GNU Affero General Public License
 along with this program.  If not, see <http://www.gnu.org/licenses/>.
 ***************************************/

#include <assert.h>

#include <unistd.h>
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <fcntl.h>
#include <errno.h>
#include <sys/stat.h>
#include <sys/mman.h>
#include <sys/types.h>

#include "files.h"


/*+ A structure to contain the list of memory mapped files. +*/
struct mmapinfo
{
 const char  *filename;         /*+ The name of the file (the index of the list). +*/
       int    fd;               /*+ The file descriptor used when it was opened. +*/
       void  *address;          /*+ The address the file was mapped to. +*/
       size_t length;           /*+ The length of the file. +*/
};

/*+ The list of memory mapped files. +*/
static struct mmapinfo *mappedfiles;

/*+ The number of mapped files. +*/
static int nmappedfiles=0;


/*++++++++++++++++++++++++++++++++++++++
  Return a filename composed of the dirname, prefix and filename.

  char *FileName Returns an allocated filename.

  const char *dirname The directory name.

  const char *prefix The file prefix.

  const char *name The filename.
  ++++++++++++++++++++++++++++++++++++++*/

char *FileName(const char *dirname,const char *prefix, const char *name)
{
 char *filename=(char*)malloc((dirname?strlen(dirname):0)+1+(prefix?strlen(prefix):0)+1+strlen(name));

 sprintf(filename,"%s%s%s%s%s",dirname?dirname:"",dirname?"/":"",prefix?prefix:"",prefix?"-":"",name);

 return(filename);
}


/*++++++++++++++++++++++++++++++++++++++
  Open a file and map it into memory.

  void *MapFile Returns the address of the file or exits in case of an error.

  const char *filename The name of the file to open.
  ++++++++++++++++++++++++++++++++++++++*/

void *MapFile(const char *filename)
{
 int fd;
 off_t size;
 void *address;

 /* Open the file and get its size */

 fd=ReOpenFile(filename);

 size=SizeFile(filename);

 /* Map the file */

 address=mmap(NULL,size,PROT_READ,MAP_SHARED,fd,0);

 if(address==MAP_FAILED)
   {
    close(fd);

    assert(0);

    fprintf(stderr,"Cannot mmap file '%s' for reading [%s].\n",filename,strerror(errno));
    exit(EXIT_FAILURE);
   }

 mappedfiles=(struct mmapinfo*)realloc((void*)mappedfiles,(nmappedfiles+1)*sizeof(struct mmapinfo));

 mappedfiles[nmappedfiles].filename=filename;
 mappedfiles[nmappedfiles].fd=fd;
 mappedfiles[nmappedfiles].address=address;
 mappedfiles[nmappedfiles].length=size;

 nmappedfiles++;

 return(address);
}


/*++++++++++++++++++++++++++++++++++++++
  Open a file and map it into memory.

  void *MapFile Returns the address of the file or exits in case of an error.

  const char *filename The name of the file to open.
  ++++++++++++++++++++++++++++++++++++++*/

void *MapFileWriteable(const char *filename)
{
 int fd;
 off_t size;
 void *address;

 /* Open the file and get its size */

 fd=ReOpenFileWriteable(filename);

 size=SizeFile(filename);

 /* Map the file */

 address=mmap(NULL,size,PROT_READ|PROT_WRITE,MAP_SHARED,fd,0);

 if(address==MAP_FAILED)
   {
    close(fd);

    fprintf(stderr,"Cannot mmap file '%s' for reading and writing [%s].\n",filename,strerror(errno));
    exit(EXIT_FAILURE);
   }

 mappedfiles=(struct mmapinfo*)realloc((void*)mappedfiles,(nmappedfiles+1)*sizeof(struct mmapinfo));

 mappedfiles[nmappedfiles].filename=filename;
 mappedfiles[nmappedfiles].fd=fd;
 mappedfiles[nmappedfiles].address=address;
 mappedfiles[nmappedfiles].length=size;

 nmappedfiles++;

 return(address);
}


/*++++++++++++++++++++++++++++++++++++++
  Unmap a file.

  void *UnmapFile Returns NULL (for similarity to the MapFile function).

  const char *filename The name of the file when it was opened.
  ++++++++++++++++++++++++++++++++++++++*/

void *UnmapFile(const char *filename)
{
 int i;

 for(i=0;i<nmappedfiles;i++)
    if(!strcmp(mappedfiles[i].filename,filename))
       break;

 if(i==nmappedfiles)
   {
    fprintf(stderr,"The file '%s' was not mapped using MapFile().\n",filename);
    exit(EXIT_FAILURE);
   }

 /* Close the file */

 close(mappedfiles[i].fd);

 /* Unmap the file */

 munmap(mappedfiles[i].address,mappedfiles[i].length);

 /* Shuffle the list of files */

 nmappedfiles--;

 if(nmappedfiles>i)
    memmove(&mappedfiles[i],&mappedfiles[i+1],(nmappedfiles-i)*sizeof(struct mmapinfo));

 return(NULL);
}


/*++++++++++++++++++++++++++++++++++++++
  Open a new file on disk for writing to.

  int OpenFile Returns the file descriptor if OK or exits in case of an error.

  const char *filename The name of the file to create.
  ++++++++++++++++++++++++++++++++++++++*/

int OpenFileNew(const char *filename)
{
 int fd;

 /* Open the file */

 fd=open(filename,O_RDWR|O_CREAT|O_TRUNC,S_IRUSR|S_IWUSR|S_IRGRP|S_IROTH);

 if(fd<0)
   {
    fprintf(stderr,"Cannot open file '%s' for writing [%s].\n",filename,strerror(errno));
    exit(EXIT_FAILURE);
   }

 return(fd);
}


/*++++++++++++++++++++++++++++++++++++++
  Open a new file on disk for reading from and appending.

  int OpenFileAppend Returns the file descriptor if OK or exits in case of an error.

  const char *filename The name of the file to create.
  ++++++++++++++++++++++++++++++++++++++*/

int OpenFileAppend(const char *filename)
{
 int fd;

 /* Open the file */

 fd=open(filename,O_RDWR|O_CREAT|O_APPEND,S_IRUSR|S_IWUSR|S_IRGRP|S_IROTH);

 if(fd<0)
   {
    fprintf(stderr,"Cannot open file '%s' for appending [%s].\n",filename,strerror(errno));
    exit(EXIT_FAILURE);
   }

 return(fd);
}


/*++++++++++++++++++++++++++++++++++++++
  Open an existing file on disk for reading.

  int ReOpenFile Returns the file descriptor if OK or exits in case of an error.

  const char *filename The name of the file to open.
  ++++++++++++++++++++++++++++++++++++++*/

int ReOpenFile(const char *filename)
{
 int fd;

 /* Open the file */

 fd=open(filename,O_RDONLY);

 if(fd<0)
   {
    fprintf(stderr,"Cannot open file '%s' for reading [%s].\n",filename,strerror(errno));
    exit(EXIT_FAILURE);
   }

 return(fd);
}


/*++++++++++++++++++++++++++++++++++++++
  Open an existing file on disk for reading from or writing to.

  int ReOpenFileWriteable Returns the file descriptor if OK or exits in case of an error.

  const char *filename The name of the file to open.
  ++++++++++++++++++++++++++++++++++++++*/

int ReOpenFileWriteable(const char *filename)
{
 int fd;

 /* Open the file */

 fd=open(filename,O_RDWR);

 if(fd<0)
   {
    fprintf(stderr,"Cannot open file '%s' for reading and writing [%s].\n",filename,strerror(errno));
    exit(EXIT_FAILURE);
   }

 return(fd);
}


/*++++++++++++++++++++++++++++++++++++++
  Get the size of a file.

  off_t SizeFile Returns the file size.

  const char *filename The name of the file to check.
  ++++++++++++++++++++++++++++++++++++++*/

off_t SizeFile(const char *filename)
{
 struct stat buf;

 if(stat(filename,&buf))
   {
    fprintf(stderr,"Cannot stat file '%s' [%s].\n",filename,strerror(errno));
    exit(EXIT_FAILURE);
   }

 return(buf.st_size);
}


/*++++++++++++++++++++++++++++++++++++++
  Check if a file exists.

  int ExistsFile Returns 1 if the file exists and 0 if not.

  const char *filename The name of the file to check.
  ++++++++++++++++++++++++++++++++++++++*/

int ExistsFile(const char *filename)
{
 struct stat buf;

 if(stat(filename,&buf))
    return(0);
 else
    return(1);
}


/*++++++++++++++++++++++++++++++++++++++
  Close a file on disk.

  int fd The file descriptor to close.
  ++++++++++++++++++++++++++++++++++++++*/

void CloseFile(int fd)
{
 close(fd);
}


/*++++++++++++++++++++++++++++++++++++++
  Delete a file from disk.

  int DeleteFile Returns 0 if OK or something else in case of an error.

  char *filename The name of the file to delete.
  ++++++++++++++++++++++++++++++++++++++*/

int DeleteFile(char *filename)
{
 unlink(filename);

 return(0);
}
1	/***************************************
2	$Header: /home/amb/CVS/routino/src/files.c,v 1.23 2010-10-09 18:20:18 amb Exp $
3
4	Functions to handle files.
5
6	Part of the Routino routing software.
7	****************/ /****************
8	This file Copyright 2008-2010 Andrew M. Bishop
9
10	This program is free software: you can redistribute it and/or modify
11	it under the terms of the GNU Affero General Public License as published by
12	the Free Software Foundation, either version 3 of the License, or
13	(at your option) any later version.
14
15	This program is distributed in the hope that it will be useful,
16	but WITHOUT ANY WARRANTY; without even the implied warranty of
17	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
18	GNU Affero General Public License for more details.
19
20	You should have received a copy of the GNU Affero General Public License
21	along with this program. If not, see <http://www.gnu.org/licenses/>.
22	***************************************/
23
24	#include <assert.h>
25
26	#include <unistd.h>
27	#include <stdlib.h>
28	#include <stdio.h>
29	#include <string.h>
30	#include <fcntl.h>
31	#include <errno.h>
32	#include <sys/stat.h>
33	#include <sys/mman.h>
34	#include <sys/types.h>
35
36	#include "files.h"
37
38
39	/+ A structure to contain the list of memory mapped files. +/
40	struct mmapinfo
41	{
42	const char filename; /+ The name of the file (the index of the list). +*/
43	int fd; /+ The file descriptor used when it was opened. +/
44	void address; /+ The address the file was mapped to. +*/
45	size_t length; /+ The length of the file. +/
46	};
47
48	/+ The list of memory mapped files. +/
49	static struct mmapinfo *mappedfiles;
50
51	/+ The number of mapped files. +/
52	static int nmappedfiles=0;
53
54
55	/*++++++++++++++++++++++++++++++++++++++
56	Return a filename composed of the dirname, prefix and filename.
57
58	char *FileName Returns an allocated filename.
59
60	const char *dirname The directory name.
61
62	const char *prefix The file prefix.
63
64	const char *name The filename.
65	++++++++++++++++++++++++++++++++++++++*/
66
67	char FileName(const char dirname,const char prefix, const char name)
68	{
69	char filename=(char)malloc((dirname?strlen(dirname):0)+1+(prefix?strlen(prefix):0)+1+strlen(name));
70
71	sprintf(filename,"%s%s%s%s%s",dirname?dirname:"",dirname?"/":"",prefix?prefix:"",prefix?"-":"",name);
72
73	return(filename);
74	}
75
76
77	/*++++++++++++++++++++++++++++++++++++++
78	Open a file and map it into memory.
79
80	void *MapFile Returns the address of the file or exits in case of an error.
81
82	const char *filename The name of the file to open.
83	++++++++++++++++++++++++++++++++++++++*/
84
85	void MapFile(const char filename)
86	{
87	int fd;
88	off_t size;
89	void *address;
90
91	/* Open the file and get its size */
92
93	fd=ReOpenFile(filename);
94
95	size=SizeFile(filename);
96
97	/* Map the file */
98
99	address=mmap(NULL,size,PROT_READ,MAP_SHARED,fd,0);
100
101	if(address==MAP_FAILED)
102	{
103	close(fd);
104
105	assert(0);
106
107	fprintf(stderr,"Cannot mmap file '%s' for reading [%s].\n",filename,strerror(errno));
108	exit(EXIT_FAILURE);
109	}
110
111	mappedfiles=(struct mmapinfo)realloc((void)mappedfiles,(nmappedfiles+1)*sizeof(struct mmapinfo));
112
113	mappedfiles[nmappedfiles].filename=filename;
114	mappedfiles[nmappedfiles].fd=fd;
115	mappedfiles[nmappedfiles].address=address;
116	mappedfiles[nmappedfiles].length=size;
117
118	nmappedfiles++;
119
120	return(address);
121	}
122
123
124	/*++++++++++++++++++++++++++++++++++++++
125	Open a file and map it into memory.
126
127	void *MapFile Returns the address of the file or exits in case of an error.
128
129	const char *filename The name of the file to open.
130	++++++++++++++++++++++++++++++++++++++*/
131
132	void MapFileWriteable(const char filename)
133	{
134	int fd;
135	off_t size;
136	void *address;
137
138	/* Open the file and get its size */
139
140	fd=ReOpenFileWriteable(filename);
141
142	size=SizeFile(filename);
143
144	/* Map the file */
145
146	address=mmap(NULL,size,PROT_READ\|PROT_WRITE,MAP_SHARED,fd,0);
147
148	if(address==MAP_FAILED)
149	{
150	close(fd);
151
152	fprintf(stderr,"Cannot mmap file '%s' for reading and writing [%s].\n",filename,strerror(errno));
153	exit(EXIT_FAILURE);
154	}
155
156	mappedfiles=(struct mmapinfo)realloc((void)mappedfiles,(nmappedfiles+1)*sizeof(struct mmapinfo));
157
158	mappedfiles[nmappedfiles].filename=filename;
159	mappedfiles[nmappedfiles].fd=fd;
160	mappedfiles[nmappedfiles].address=address;
161	mappedfiles[nmappedfiles].length=size;
162
163	nmappedfiles++;
164
165	return(address);
166	}
167
168
169	/*++++++++++++++++++++++++++++++++++++++
170	Unmap a file.
171
172	void *UnmapFile Returns NULL (for similarity to the MapFile function).
173
174	const char *filename The name of the file when it was opened.
175	++++++++++++++++++++++++++++++++++++++*/
176
177	void UnmapFile(const char filename)
178	{
179	int i;
180
181	for(i=0;i<nmappedfiles;i++)
182	if(!strcmp(mappedfiles[i].filename,filename))
183	break;
184
185	if(i==nmappedfiles)
186	{
187	fprintf(stderr,"The file '%s' was not mapped using MapFile().\n",filename);
188	exit(EXIT_FAILURE);
189	}
190
191	/* Close the file */
192
193	close(mappedfiles[i].fd);
194
195	/* Unmap the file */
196
197	munmap(mappedfiles[i].address,mappedfiles[i].length);
198
199	/* Shuffle the list of files */
200
201	nmappedfiles--;
202
203	if(nmappedfiles>i)
204	memmove(&mappedfiles[i],&mappedfiles[i+1],(nmappedfiles-i)*sizeof(struct mmapinfo));
205
206	return(NULL);
207	}
208
209
210	/*++++++++++++++++++++++++++++++++++++++
211	Open a new file on disk for writing to.
212
213	int OpenFile Returns the file descriptor if OK or exits in case of an error.
214
215	const char *filename The name of the file to create.
216	++++++++++++++++++++++++++++++++++++++*/
217
218	int OpenFileNew(const char *filename)
219	{
220	int fd;
221
222	/* Open the file */
223
224	fd=open(filename,O_RDWR\|O_CREAT\|O_TRUNC,S_IRUSR\|S_IWUSR\|S_IRGRP\|S_IROTH);
225
226	if(fd<0)
227	{
228	fprintf(stderr,"Cannot open file '%s' for writing [%s].\n",filename,strerror(errno));
229	exit(EXIT_FAILURE);
230	}
231
232	return(fd);
233	}
234
235
236	/*++++++++++++++++++++++++++++++++++++++
237	Open a new file on disk for reading from and appending.
238
239	int OpenFileAppend Returns the file descriptor if OK or exits in case of an error.
240
241	const char *filename The name of the file to create.
242	++++++++++++++++++++++++++++++++++++++*/
243
244	int OpenFileAppend(const char *filename)
245	{
246	int fd;
247
248	/* Open the file */
249
250	fd=open(filename,O_RDWR\|O_CREAT\|O_APPEND,S_IRUSR\|S_IWUSR\|S_IRGRP\|S_IROTH);
251
252	if(fd<0)
253	{
254	fprintf(stderr,"Cannot open file '%s' for appending [%s].\n",filename,strerror(errno));
255	exit(EXIT_FAILURE);
256	}
257
258	return(fd);
259	}
260
261
262	/*++++++++++++++++++++++++++++++++++++++
263	Open an existing file on disk for reading.
264
265	int ReOpenFile Returns the file descriptor if OK or exits in case of an error.
266
267	const char *filename The name of the file to open.
268	++++++++++++++++++++++++++++++++++++++*/
269
270	int ReOpenFile(const char *filename)
271	{
272	int fd;
273
274	/* Open the file */
275
276	fd=open(filename,O_RDONLY);
277
278	if(fd<0)
279	{
280	fprintf(stderr,"Cannot open file '%s' for reading [%s].\n",filename,strerror(errno));
281	exit(EXIT_FAILURE);
282	}
283
284	return(fd);
285	}
286
287
288	/*++++++++++++++++++++++++++++++++++++++
289	Open an existing file on disk for reading from or writing to.
290
291	int ReOpenFileWriteable Returns the file descriptor if OK or exits in case of an error.
292
293	const char *filename The name of the file to open.
294	++++++++++++++++++++++++++++++++++++++*/
295
296	int ReOpenFileWriteable(const char *filename)
297	{
298	int fd;
299
300	/* Open the file */
301
302	fd=open(filename,O_RDWR);
303
304	if(fd<0)
305	{
306	fprintf(stderr,"Cannot open file '%s' for reading and writing [%s].\n",filename,strerror(errno));
307	exit(EXIT_FAILURE);
308	}
309
310	return(fd);
311	}
312
313
314	/*++++++++++++++++++++++++++++++++++++++
315	Get the size of a file.
316
317	off_t SizeFile Returns the file size.
318
319	const char *filename The name of the file to check.
320	++++++++++++++++++++++++++++++++++++++*/
321
322	off_t SizeFile(const char *filename)
323	{
324	struct stat buf;
325
326	if(stat(filename,&buf))
327	{
328	fprintf(stderr,"Cannot stat file '%s' [%s].\n",filename,strerror(errno));
329	exit(EXIT_FAILURE);
330	}
331
332	return(buf.st_size);
333	}
334
335
336	/*++++++++++++++++++++++++++++++++++++++
337	Check if a file exists.
338
339	int ExistsFile Returns 1 if the file exists and 0 if not.
340
341	const char *filename The name of the file to check.
342	++++++++++++++++++++++++++++++++++++++*/
343
344	int ExistsFile(const char *filename)
345	{
346	struct stat buf;
347
348	if(stat(filename,&buf))
349	return(0);
350	else
351	return(1);
352	}
353
354
355	/*++++++++++++++++++++++++++++++++++++++
356	Close a file on disk.
357
358	int fd The file descriptor to close.
359	++++++++++++++++++++++++++++++++++++++*/
360
361	void CloseFile(int fd)
362	{
363	close(fd);
364	}
365
366
367	/*++++++++++++++++++++++++++++++++++++++
368	Delete a file from disk.
369
370	int DeleteFile Returns 0 if OK or something else in case of an error.
371
372	char *filename The name of the file to delete.
373	++++++++++++++++++++++++++++++++++++++*/
374
375	int DeleteFile(char *filename)
376	{
377	unlink(filename);
378
379	return(0);
380	}